Tag Archives: Queensland Museum

New tropical island yabbies discovered

While the impact of development on our coastal habitats is a topic constantly in the news, it’s sobering to be reminded that we are still finding out what species of plants and animals actually live in these fragile places.

Cherax austini, one of two recently described species of freshwater crayfish from Whitsunday Island. Preserved specimen, photo R. Ashdown.

For zoologists, the discovery of a new species is always significant. It’s like finding another piece in the threatened and fragile jigsaw of life that surrounds us and on which we depend so much.

The Whitsunday Ngaro Sea Trail is a mix of seaways and picturesque walks across Whitsunday, South Molle and Hook islands. The walk leads through open forests, grasslands and rainforest, and includes climbs up rugged peaks and strolls along winding pathways.

Created by the Queensland Parks and Wildlife Service (QPWS), the walking tracks and other infrastructure associated with the Sea Trail were yet more ‘development’. So, before this project was completed, a careful analysis of any associated impacts was carried out, to make sure they’d be kept as small as possible. As a part of that process, new surveys of the fauna and flora of Whitsunday Island were completed.

In 2010, while undertaking one of these surveys, QPWS employees Rod Hobson and Richard Johnson discovered the remains of a freshwater crayfish Cherax sp. These were forwarded to crayfish researcher Jason Coughran for comment. Jason recognised these remains to be those of a yet undescribed species. A return trip was arranged to collect live specimens for description, which was duly accomplished later that year. During this trip a second species of freshwater crayfish was also found on the island.

Rod Hobson and Richard Johnson in pursuit of an interesting reptile. Yelarbon. Photo R. Ashdown.

Rod Hobson and Richard Johnson in pursuit of an interesting reptile on a QPWS fauna survey, Yelarbon, 2006. Photo R. Ashdown.

These crustaceans have now been formally recognised as two new species — Cherax austini sp. n. Coughran & Hobson and Cherax cid sp. n. Dawkins & Furse (Coughran et al 2012).

Cherax austini (left) and Cherax cid (right). These specimens are the holotypes of the two new species, stored permanently in the collections of the Queensland Museum. The museum’s zoological collections represent the ever-growing and priceless database of Queensland’s faunal diversity. [A holotype is the actual physical specimen of an organism that was used when the species was officially described]. Photo courtesy Queensland Museum.

Freshwater crayfish, known variously as yabbies, lobbies, crawchies, craybobs, craydads, marron, gilgies and koonacs, are creatures well known across Australia. There are over a 100 species (family Parastacidae) in Australia, with more than 20 native to Queensland, including one of the smallest in the world (the Swamp Crayfish Tenuibranchiurus glypticus, which reaches about 25 mm in length — by contrast, the Giant Tasmanian Crayfish Astacopsis gouldii reaches up to about 4.5 kg in weight and is the world’s largest freshwater crayfish — see * below)

SWAMP CRAYFISH, TENIBRANCHIURUS GLYPTICUS. Thorneside.

The Swamp Crayfish (Tenibranchiurus glypticus), at about 2.5 cm in length, is one of the world’s smallest freshwater crayfish. Thorneside, Brisbane. Photo R. Ashdown.

Queensland species belong to three genera: Cherax (smooth freshwater crayfish or freshwater yabbies); Euastacus (spiny freshwater crayfish) and Tenuibranchiurus (swamp crayfish).

According to the authors of the paper on these two new Cherax species, there is no information on any other species of freshwater crayfish inhabiting islands this far north in the Coral Sea, apart from a single specimen of the Orange-fingered Yabby Cherax depressus collected at Lindemann Island about 12 km south of Whitsunday Island. The next closest island species is the Sand Yabby Cherax robustus, found on Fraser Island, about 700 km south. Interestingly, Cherax austini displays a feature (a median ridge on the cephalon) that is associated with crayfish in the extreme south-west of Western Australia (Coughran et al 2012).

The results of genetic work on the two new species, however, show that they are related to the mainland Cherax depressus group of yabbies, but as with island species of all types, they are busy evolving down their own divergent paths.

An Orange-fingered Yabby (Cherax depressus), roaming around a walking track like a small armoured tank after heavy rain at Lota, Brisbane. Photo R. Ashdown.

Euastacus suttoni, a colourful member of the spiny crayfish group, strikes a defensive pose as the terrifying photographer approaches. Bald Rock National Park, New South Wales. Photo R. Ashdown.

While probably confined to Whitsunday Island, the discovery of these two new species highlights the importance of continuing surveys on other Coral Sea Islands. There aren’t many suitable wetlands on Whitsunday Island, so checking out ephemeral wetlands and drainages on other islands in the group may just reveal further new creatures.

When species are restricted to islands, careful management is needed, as they are potentially vulnerable to various human-induced and naturally-occuring impacts. The value of national parks for protecting biodiversity is once again underlined. Cherax austini was discovered in a single Melaleuca (paperbark) swamp, a particular type of habitat that is classified as an “endangered” Regional Ecosystem. This particular location is one of only four protected areas of this habitat type in Queensland. The specimen was first detected as shell remains in midden formations around the shoreline of the swamp, probably from a predator such as an Eastern Water Rat.

Cherax cid was found in a small, clear flowing stream within notophyll vine forest, a type of coastal rainforest scrub. The specific type of Regional Ecosystem that this locality fell within is found only within six protected areas in Queensland.

The discovery of new species of such well-known creatures as yabbies is a pleasant surprise. It’s a find that once more increases our understanding of the the size and beauty of Australia’s biological diversity — our irreplaceable natural heritage.

The Common yabby (Cherax destructor), a well-known (and dined-upon) crustacean of the Australian west. Lake Broadwater Conservation Park, near Dalby, Darling Downs. Photo R. Ashdown.

*The large and the small (from Rod Hobson, 7/4/2013)

It has long been a matter of Aussie pride among those of us interested in our freshwater crayfish (from perspectives other than gastronomic) that we have both the largest and smallest freshwater yabby in the world. Whilst there is no argument whatsoever about our having the largest our contention that we also have the smallest is hotly contested by our friends from under The Star Spangled Banner. Our local contender is the Swamp Crayfish Tenuibranchiurus glypticus, which is a Wallum denizen of south-east Queensland reaching a grandiose length of 25 mm. South of the Mason-Dixon in the Deep South of the USA the flyweight belt is claimed by the Dwarf Crayfish Cambarellus diminutus. The Dwarf Crayfish is one of 17 species of freshwater crayfish of the family Cambaridae found in Mexico and the Gulf States of the USA. This family are all generally known en masse as dwarf crayfish, or more likely as crawdads or craybobs. Crawdad and craybob have also been absorbed into the Australian vernacular for our freshwater yabbies but are actually American terms. We owe a lot to The Beverly Hillbillies.

Cambarellus diminutus is a rare and threatened species known only from about 15 locations in Mobile County, Alabama and Jackson and George Counties in Mississippi. This crawdad also reaches an upper length of 25 mm so it’s actually a photofinish for the title of the world’s smallest crayfish. It’s a tie and we cannot, in all fairness, claim our crustacean, as the world’s smallest yabby. We still, however have a “no contest” for the world’s largest in the Tasmanian Giant Crayfish Astacopsis gouldi tipping the scales at 5 kilograms wringing wet and attaining a length of 80 cms. In fact not only is Astacopsis the world’s largest freshwater crayfish it is actually the world’s largest freshwater invertebrate. Let’s see someone beat that one!

Reference:

Coughran Jason, Dawkins Kathryn L., Hobson Rod and Furse James M., 2012. ‘Two new freshwater crayfishes (Decapoda: Parastacidae) from Whitsunday Island, The Coral Sea, Australia’ in Crustacean Research, Special Number 7, 45-51, 2012.

Links

The Queensland Museum’s freshwater crayfish fact shee t (PDF download)
The Whitsunday Ngaro Sea Trail

Riders on the storm

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Queensland is still counting the cost of ‘ex-Tropical Cyclone Oswald’, with major flooding and damage to property and infrastructure right down the east coast.

Humans were not the only species affected, with seabirds being blown far from home by the wild weather during January 2013.

Black Noddy, photographed at Shorncliffe by Mike Peisley. Blown off course by Cyclone Oswald, this is a bird usually found on islands and cays, including the Capricorn and Bunker groups, the Great Barrier Reef, Norfolk Island and the Coral Sea. It’s a species that occasionally visits Stradbroke Island and eastern New South Wales.

In the Darling Downs area, a range of unusual species were recorded. Birds either seen flying or found exhausted included Wedge-tailed Shearwaters, Sooty Terns, White-tailed Tropicbirds, Frigatebirds and a Bulwer’s Petrel. The latter was a very interesting record — although there have been several confirmed sightings of Bulwer’s Petrels in Queensland over the years, this was the first specimen of this species obtained for the State, and only the second specimen for Australia.

White-tailed Tropicbird 2 Mick Atzeni copy

White-tailed Tropicbird, found in Toowoomba — a long way from ‘home’. This is a true ocean-going bird (pelagic), only coming ashore to breed. For eastern Australian birds, breeding takes place at Fiji – New Caledonia and the Tuamotu and Walpole islands. Photograph courtesy Mick Atzeni.

Toowoomba Bird Observers (TBO) president Mick Atzeni has been collecting records of the unusual sightings, adding to the group’s extensive database on the birds of the Toowoomba region.

“To see seabirds flying around paddocks and over local dams was a once-in-a-lifetime opportunity for most people,” said Mick. “It was bitter-sweet, because these birds were starving, exhausted, and lost.”

Wildlife carer Trish LeeHong cared for some of the exhausted birds, which stretched the resources of her always-busy and not-for-profit Wildlife Rescue, Rehabilitation and Education Association. Several were restored to health and released at Deception Bay.

Wedge-tailed Shearwater, Toowoomba. The common ‘muttonbird’ of Queensland’s warmer coastal waters, responsible for the wailing, crooning sounds often heard at night on Great Barrier Reef islands (but usually not in the Toowoomba suburbs). Photograph courtesy Pat McConnell.

Mick reported that dead Sooty Terns were found in the middle of Toowoomba, at the Murphys Creek township and at Lockyer Siding, while a Wedge-tailed Shearwater was found in James Street near Clifford Gardens, Toowoomba. Exhausted White-tailed Tropicbirds were found at Meringandan and Withcott, while Sooty Terns and a Wedge-tailed Shearwater were seen flying over the Lockyer Valley by TBO members.

Adult Sooty Tern, Toowoomba. Also known as ‘Wideawake’, the Sooty Tern’s habitat is tropical and sub-tropical seas as well as islands and coral cays. Photograph courtesy Mick Atzeni.

Juvenile Sooty Tern, Lota. Photograph courtesy James Hunt.

“Wedge-tailed Shearwater and White-tailed Tropicbird are new birds for the official TBO bird list,” said Mick. “This was our first live record for Sooty Terns in the area we survey, as the only previous record was a dead one found on the Range Highway in 1976 (during a previous cyclone).”

The body of the Bulwer’s Petrel, which unfortunately died soon after being found, was lodged with the Queensland Museum at Southbank, where its identity was confirmed. Stored as part of the Museum’s natural history collections, the specimen will be valuable for future studies.

Bulwer’s Petrel, collected at the Oakey Army Base, on the Darling Downs. This small, sooty-brown seabird is found in tropical and sub-tropical waters around the world. Usually a solitary bird when at sea, this species gathers to breed on islands in the Pacific and north Atlantic oceans. Bulwer’s Petrels have only been sighted in Australian waters on several occasions. Photo R. Ashdown.

Ian Gynther, Senior Conservation Officer with the Department of Environment and Heritage Protection, spoke to the ABC about the Bulwer’s Petrel. “It’s only a tiny thing. When they’re not breeding they spend their whole life at sea — you could imagine the waves and wind they put up with at the best of times.”

“This is a prime example of how our knowledge of a bird that’s seldom recorded has been greatly increased by somebody with sharp eyes at Oakey,” said Ian.

Black Noddy on the wing at Shorncliffe — grace, style and frequent flyer points. Photograph courtesy Mike Peisley.

Hmmm … maybe not so much grace, but a survivor nonetheless. Storm-battered Torresian Crow, Shorncliffe. Photo courtesy Mike Peisley.

Find out more about The Toowoomba Bird Observers.

Thanks to Mick Atzeni, Mike Peisley, James Hunt, Pat McConnell and Rod Hobson.

Frogs and lizards in print

March of the Mysterious Moon Ants

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The mysterious twilight procession begins. Up the driveway, across some steps and along our paved area with relentless purpose. Photos taken by Rob and Harry Ashdown on Canon Powershot G10 and G12.

Every summer, about twilight, when the throaty rumble of newly-emerged Bladder Cicadas fills our ears, a strange procession happens outside our back door. Large ants wander up from the driveway, always heading in the same direction — across the back paved area in the direction of our neighbours’ house.

Banded Sugar Ants on the go. Sugar Ants come in many shapes and sizes, and are named after their habit of collecting sugary plant secretions, although most species are also scavengers and predators. Many Brisbane species are nocturnal.

We’ve come to call them Moon Ants, for some reason, probably because they come out only at night, and we’ve watched them in the moonlight (as you do). We quizzed Susan about them when she visited a few years back. Susan’s a guru of all things entomological, which she should be, as she’s an entomologist at the Queensland Museum in Brisbane. She filled us in. These are Banded Sugar Ants (Camponotis consobrinus), members of the largest genus of ants in the world, a group that comprises thousands of species, of which at least 20 are found in the Brisbane area.

Sugar Ants differ from other ants in several ways, according to the Queensland Museum’s wonderful guide to ants (seriously, this is a fabulous book). Most have no metapleural gland (you knew that I’m sure), and they lack its associated opening above the base of the hind leg (you probably knew that too). There’s more. They have a single segmented waist and the mesosoma and petiole lack spines (I knew that … well, I do now). Workers don’t sting, but can spray formic acid into a bitten area. Ouch!

Although big and fierce looking, Banded Sugar Ants don’t sting, but they can bite, although we’ve yet to be savaged by any. They fare rather worse in our encounters, often getting flattened by foot traffic out the back at night.

A Banded Sugar Ant pauses to inspect the body of an unfortunate colleague, tragically flattened by the giant feet of blundering humans.

Last year we went on a mission to track down their nest site, which we found under some old railway sleepers alongside the driveway. We didn’t disturb them, and although most people have a fair amount of disdain, or even hostility, for ants, I reckon they are terrific. We always like watching their purposeful march past our back stairs. Another piece in the jigsaw of our strangely diverse suburban backyard.

More about Sugar Ants, and everything else, from the Queensland Museum’s website.
A fabulous book about Brisbane’s ants, from the same bunch of natural history gurus. Written, with clear enthusiasm and riddled with an abundance of fascinating facts, by Dr Chris Burwell — and with insanely good photography by one of my favourite photographers (and old mate) Jeff Wright. A must-read for any natural historian.